/*
 * File    : TrackersUtil.java
 * Created : 7 nov. 2003 12:09:56
 * By      : Olivier 
 * 
 * Azureus - a Java Bittorrent client
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details ( see the LICENSE file ).
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.gudy.azureus2.core3.util;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

/**
 * @author Olivier
 * 
 */
public class TrackersUtil {

    private List<String> trackers;
    private Map<String, List<List<String>>> multiTrackers;
    private Map<String, Map> webseeds;

    private static TrackersUtil instance;
    private static AEMonitor class_mon = new AEMonitor("TrackersUtil:class");

    private TrackersUtil() {
        trackers = new ArrayList<String>();
        multiTrackers = new HashMap<String, List<List<String>>>();
        webseeds = new HashMap<String, Map>();
        loadList();
    }

    public static TrackersUtil getInstance() {
        try {
            class_mon.enter();

            if (instance == null)
                instance = new TrackersUtil();
            return instance;

        } finally {

            class_mon.exit();
        }
    }

    public List<String> getTrackersList() {
        if (trackers != null)
            return new ArrayList<String>(trackers);
        else
            return null;
    }

    public void addTracker(String trackerAnnounceUrl) {
        if (trackers.contains(trackerAnnounceUrl))
            return;
        trackers.add(0, trackerAnnounceUrl);
        saveList();
    }

    public void addMultiTracker(String configName, List<List<String>> groups) {
        multiTrackers.put(configName, groups);
        saveList();
    }

    public void removeMultiTracker(String configName) {
        multiTrackers.remove(configName);
        saveList();
    }

    public Map<String, List<List<String>>> getMultiTrackers() {
        return new HashMap<String, List<List<String>>>(multiTrackers);
    }

    public void addWebSeed(String configName, Map ws) {
        webseeds.put(configName, ws);
        saveList();
    }

    public void removeWebSeed(String configName) {
        webseeds.remove(configName);
        saveList();
    }

    public Map<String, Map> getWebSeeds() {
        return new HashMap<String, Map>(webseeds);
    }

    public void clearAllTrackers(boolean save) {
        trackers = new ArrayList<String>();
        multiTrackers = new HashMap<String, List<List<String>>>();
        webseeds = new HashMap<String, Map>();
        if (save) {
            saveList();
        }
    }

    private void loadList() {
        File fTrackers = FileUtil.getUserFile("trackers.config");
        if (fTrackers.exists() && fTrackers.isFile()) {
            FileInputStream fin = null;
            BufferedInputStream bin = null;
            try {
                fin = new FileInputStream(fTrackers);
                bin = new BufferedInputStream(fin, 8192);
                Map map = BDecoder.decode(bin);
                List list = (List) map.get("trackers");
                if (list != null) {
                    Iterator iter = list.iterator();
                    while (iter.hasNext()) {
                        String tracker = new String((byte[]) iter.next());
                        trackers.add(tracker);
                    }
                }
                Map mapMT = (Map) map.get("multi-trackers");
                if (mapMT != null) {
                    Iterator iter = mapMT.keySet().iterator();
                    while (iter.hasNext()) {
                        String configName = (String) iter.next();
                        List groups = (List) mapMT.get(configName);
                        List resGroups = new ArrayList(groups.size());
                        Iterator iterGroups = groups.iterator();
                        while (iterGroups.hasNext()) {
                            List theseTrackers = (List) iterGroups.next();
                            List resTrackers = new ArrayList(theseTrackers.size());
                            Iterator iterTrackers = theseTrackers.iterator();
                            while (iterTrackers.hasNext()) {
                                String tracker = new String((byte[]) iterTrackers.next());
                                resTrackers.add(tracker);
                            }
                            resGroups.add(resTrackers);
                        }
                        this.multiTrackers.put(configName, resGroups);
                    }
                }
                webseeds = (Map) map.get("webseeds");

                if (webseeds == null) {
                    webseeds = new HashMap();
                } else {
                    BDecoder.decodeStrings(webseeds);
                }
            } catch (Exception e) {

                Debug.printStackTrace(e);

            } finally {

                if (bin != null) {
                    try {
                        bin.close();
                    } catch (Throwable e) {
                    }
                }
                if (fin != null) {
                    try {
                        fin.close();
                    } catch (Throwable e) {
                    }
                }
            }
        }
    }

    private void saveList() {
        Map map = new HashMap();
        map.put("trackers", trackers);
        map.put("multi-trackers", multiTrackers);
        map.put("webseeds", webseeds);
        FileOutputStream fos = null;
        try {
            // Open the file
            File fTrackers = FileUtil.getUserFile("trackers.config");
            fos = new FileOutputStream(fTrackers);
            fos.write(BEncoder.encode(map));
            fos.close();
        } catch (Exception e) {
            Debug.printStackTrace(e);
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (Throwable e) {
                }
            }
        }
    }

}
